400000000840 has 32 divisors (see below), whose sum is σ = 981818184960. Its totient is φ = 145454545600.

The previous prime is 400000000819. The next prime is 400000000847. The reversal of 400000000840 is 48000000004.

It is not an unprimeable number, because it can be changed into a prime (400000000847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 454545016 + ... + 454545895.

It is an arithmetic number, because the mean of its divisors is an integer number (30681818280).

Almost surely, 2^400000000840 is an apocalyptic number.

400000000840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400000000840 is an abundant number, since it is smaller than the sum of its proper divisors (581818184120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400000000840 is a wasteful number, since it uses less digits than its factorization.

400000000840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 909090933 (or 909090929 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 400000000840 its reverse (48000000004), we get a palindrome (448000000844).

The spelling of 400000000840 in words is "four hundred billion, eight hundred forty", and thus it is an aban number.